Plywood barrel



Dec. 26, i944. C. U GRAMELsPAcHz-:R l 2,365,754

I PLYwooD BARREL Filed Feb. l2, 1942 2 Sheets-Sheet 1 2 u. GRAMELSPACHER 2,3%754 -PLYWOOD BARREL Filed Feb. l2, 1942 .2 Sheets-Sheet 2 @Ilegal CLAQENCE u GnAMELspPCl-IER 6M BY Johan/JOM ATTORNEYS Patented Dec. 26, 1944 UNITED TTES PATENTv @ENCE PLYWOD BARREL Clarence U. Gramelspacher, Jasper, Ind. Application February l2, 1942, Serial No. 430,665

(el. 14u-309) Claims.

This invention relates to a method and apparatus for manufacturing wood barrels from thin wood plies,

An object of the invention is to provide a method for manufacturing plywood barrels.

Another. object of the invention is to provide an apparatus for manufacturing plywood barrels.

Another object of the invention is to provide a method of manufacturing plywood barrels wherein the plies are so arranged with rcspect to one another that there is no dcnite seam through the barrel.

It is another object of the invention to provide a methodfor manufacturing plywood barrels of conventional shape wherein the plies, forming the wall of the barrel, are disposed in approximate position with respect to one another within a suitable form, and the plies are expanded outwardly against the form to cause adherence between the adjacent plies.

Another object of the invention is to provide a method for manufacturing plywood barrels in accordance with the foregoing object wherein the plies are cut to a predetermined configuration and assembled lwithin a suitable form.

Anotherobject of the invention is to provide a method for manufacturing plywood barrels wherein the plies, from which the barrel is to be produced have the grain thereof running 90 with respect to one another.

Another object or" the invention is to provide a method for manufacturing plywood barrels wherein pre-cut plies are assembled within a suitable form and an expansible bag is disposed within the barrel form to expand the plies against the barrel form to cause adhesion between the plies.

It is another object of the invention to provide an apparatus'for manufacturing plywood barrels which causes-the plies to be moved with respect to one another to conform roughly to the shape of a barrel, and an expansible bag finishes the forming of the barrel,

Further objects and advantages will become apparent from the drawings and the following description.

In the drawings:

Figure 1 is a perspective elevational view of a plywood barrel constructed in accordance with the teachings of this invention.

Figure 2 is a perspective elevational view of the plies for forming a sheet of plywood having the grain positioned 90 with respect to one another.

Figure 3 is a perspective elevational view of the preassembled plywood sheets precut and shown in their assembled relationship.

Figure 4 is a. perspective elevational view o the sheet of plywood rolled into a cylinder and having retaining rings thereon to hold the, same in cylindrical form.

Figure 5 is a horizontal cross-sectional view of the apparatus for forming the barrel, taken along line 5-5 of Figure 6, showing the form in open position and the cylindrical barrel disposed therein.

Figure 6 is a transverse cross-sectional view taken along line -tvof Figure, showing the form being closed upon the cylindrical barrel form.

Figure l is a horizontal cross-sectional View taken along the same line as Figure 5, showing the expansible bag expanded to cause the wood plies to conform to the mold of Figure 6.

Figure 8 is a horizontal cross-sectional view of the apparatus for forming the barrel, ,showing a filler plug within the form to llsome of the internal volume of the form.

Figure 9 is a horizontal cross-sectional view of the mold shown in Figures 5, 6 and '7, but having a filler member positioned therein for producing a barrel of slightly smaller diameter. l

Figure 10 is a cross-sectional view of a portion of a completed barrel showing the head fastened in place therein.

In this invention the applicant produces a barrel of conventional shape from a plurality of wood plies which is disposed in adjacent relationship and secured to one another by suitable means. Sheets of plywood are cut to a predetermined conguration and are then rolled into The cylinder is'then upon the cylinder to cause the precut sheets of plywood to form to the conguration of the form. Before the sheetsare rolled into the cylinder a suitable adhesive is placed upon one or both of the faces of adjacent plies. so that when placed 'in the form and expanded against the wall of the form the sheets of plywood will adhere to one another. The formed barrel is removed from the form and suitablev end walls are then secured within lthe ends of the barrel.

'I'he process of manufacture is started by first securing two sheets of plywood lll andll together having the grain of the sheets arranged with respect to one another. The sheets I0 and ll have suitable adhesive applied thereon to secure the same in4 adjacent relationship, thus forming a two-ply board. While the invention will bedescribed with regard to the use of twoply board, yet it is to be understood that indi vidual plies can be handled in the same manner as the two-ply board, or the board can be composed of more than two plies. The purpose of using boards composed of two or more plies ls sheets when bent' or formed during certain operations of the process.

The conventional barrel has a shape wherein the ends of the .barrel are smaller in diameter than the center of the barrel. Thus, to form a barrel of conventional shape from a sheet of plywood the sheet must be precut in a manner to permit .the edges of the sheet to be drawn closer together than the mid portion thereof.

In Figure 3 the two-ply board I5 is provided with a series of arcuately shaped cuts I6 extending transversely of the sheet from the edge toward the center thereof. A similar series ofcuts I1 is provided in the opposite edge of the sheet. These cutaway portions I6 and I1 are substantially V-shaped with the base of the V toward the center of the ply board I5. The bases of the 1 V-cuts I6 and I1 do not join one another and therefore the ply board I5 is not severed into into reduce the danger of splitting of the ply A dividual pieces but rather retains its original conv dition as a sheet. The V-cuts I6 and I1 have arcuate shaped sides so that .the portions between the adjacent cuts I6 form a stave I8. The staves I8 are joined to one another by means of the solid portion I9 between the bases of the V-cuts I6 and I1. y

The length of the ply board I5 is such that when rolled into the form of a cylinder the op@ posite edges 29 and 2| thereof will abut one another, thus forming a cylinder of proper diameter which will be the diameter of the completed barrel. ,k

A second ply board sheet 25 is prepared in the same manner as the ply board'sheet I5 except that the ply board sheet 25 will be slightly longer than the ply board sheet |5.4 The ply board sheet 25 is adapted to encircle the ply board sheet I 5 and hence the need for a sheet which is slightly longer than the sheet I 5. i

' The ply board sheets I5 and 25 have adhesive applied on either or both of their faces 26 and 21 respectively to cause adherence between the sheets during a subsequent operation of the process. The adhesive may be of liquid type or of a sheet type and is preferably a resinous material to produce a waterproof joint between ply board sheets.

The ply board sheet I5 is disposed upon the ply board sheet 25 in a manner that the longitudinal edges 28 and 29 are in substantial alignment and the V-cuts I6 and |1 are positioned substantially midway between the V-cuts 30 provided in the ply board sheet 25, thereby placing the V-cuts I5 and I1 upon the staves 3| of the ply board sheet 25. y

The ply board sheets I5 and 25 are then rolled into the form of a cylinder (as shown in Figure 4) the V-cuts I6 and |1 remaining adjacent the staves 3| and the V-cuts 30 being adjacent the staves I9, whereby an overlapping Joint structure from which-the barrel can be formed.

The assembled cylinder 34 is then provided with a pair of straps 35 and 36 around opposite ends thereof to draw the ends into a slightly smaller diameter than the mid portion of the cylinder 34. The cylinder 34, with the straps 35 and 36 thereon, is then placed within a form 40 which consists of two halves 31 and 38 hinged together by means of a hinge 39.

The two halves 31 and 38 forming the form 40 are semi-circular in shape so that when the member 38'is closed upon the member 31 a cylinder will be formed. A suitable latch 4| is adapted to engage a catch 42 for securing the halves31 and 38 in closed position. The halves 31 and 38 are each provided with a half ring 43 and 44 respectively which are raised from the interior surfaces 45 and 46I of the respective halves 38 and 31. The half rings 43 and 44 thereby form a complete ring when the members 31 and 38 are closed. Suitable heating passages 41 and 48 are provided in the rings 43 and 44.

A pair of cylindrical heads 49 and '50 is adapted to slide within the cylindrical form 4|), 'Ihese heads 49 and 50 have internal walls 5| and 52 which have the desired configuration for the end of a conventional barrel. Closure plates 53 and 54 are provided for the heads 49 and 59 and are connected to suitable rams 55 and 56 respectively.

The walls 5| and 52 in their respective heads 49 and V5|I are spaced from the outer walls 51 and 58 to form fluid chambers 59 and 60 respectively in the heads 49 and 50. Suitable fluid inlets 6| and 62 are provided for the chambers 59 and 60 as well as suitable outlets 63 and 64. The chambers 59 and 60 are adapted to receive fluid in any form, such as liquid or steam, for heating the ply board sheets when the heads 49 and 50 are closed upon the same. The rams 55 and 56. may be connected to any suitable source of power for reciprocating the heads 49 and 59 within the cylindrical form 40.

An expansible bag 65 is positioned within one of the heads 49 or v5|) and may be secured to the head. A suitable fluid inlet 66 is provided for the expansible bag 65 and may extend through the end wall 53 of the head 49 for connection to a suitable source of fluid pressure, such as liquid or air. The expanslble bag can be made of rubber or any other resilient material which is capable of stretching to conform to the interior configurationof the barrel to be formed within the apparatus. f

As previously mentioned the cylindrical barrel form 34 has just been positioned within the open 'cylindrical form 40 (as shown in Figure 5). The apparatus for reciprocating the rams 55 and 56 will then be operated to advance the heads 49 and 50 until they enter the member 31 a slight l distance (as shown'in Figure 5).

At this time the straps 35 and 36 are removed from the ends of the cylindrical form 34 of the barrel, whereby the ends of the barrel will engage the inner walls 5| and 52 of the heads 49 and 59.

The member 38 is then closed upon the member 31`and locked thereto by means of the latch 4|. The heads 49 and 59 are then advanced toward the center of the cylindrical form 40 until the ends thereof engage the rings 32 and 33. The staves I8 and 3| will be moved inwardly toward the axis of the barrel to conform to the contour of the walls 5| and 52 in the heads 49 and 50 respectively. When the heads 49 and 5U have completed their travel into the cylindrical form thereby producing a cylinder of proper diameter 40 the edges of adjacent staves will be in abutting relationship with respect to one another. As heretofore disclosed, the V-cuts in the sheets forming the staves have been disposed upon the stave adjacent the cut whereby the butt joint between adjacent staves will be positioned upon the face of the stave adjacent thereto above or below lthe same.

The expansible bag 65 carried by the head 49 is moved within the body of the cylindrical barrel form 34 when the head 49 contacts the end of the cylinder 34 and bends the end of the cylinder into conformity with the inner wall surface l of the head 49. A suitable fluid is then admitted into the interior of the expansible bag through the inlet opening E6 to expand the bag 65 into engagement with the inner wall surface of the cylindrical barrel form 34. The bag B5 expands the sheets of plywood in the barrel form 34 outwardly against the inner surfaces 5| and 52 of the heads 49 and 50 with one sheet in engagement with the other. This expansive movement of the plywood sheets causes .them to first slide with respect to one another so that the adjacent stave portions of the various sheets will have the adjacent joints thereof brought into proper abutting relationship.

The fluid admitted into the expansible bag G5 may be either a liquid or a gas and is preferably heated so that the internal wall of the cylindrical barrel form 34 will be heated. r

Heating fluid is circulated through the chambers 59, 60 and 48 to heat the barrel form 34 from the exterior thereof whereby the bonding material disposed between the ply board sheets will be set and cause adherence between adjacent ply board sheets.

After a suitable. period of time the expansible bag 65 is defiated and the heads M and 50 will be retracted from within the cylindrical form tu, the member 3B will be lifted from the member 3l to open the form t0 and the barrel will then be removed. The rings 32 and 33 can then be removed from the barrel 10.

The ends 6l of the barrel lll are then trimmed to the desired shape (as shown in Figure l0). A. recess 68 is cut in the inner face of the barrel lll near the edge 6l' to receive a ply board end closure wall 69.

The ply board closure wall 69 is inserted endwise into the interior of the barrel ll] and is then turned horizontally and forced into the recess 55'. Suitr` dowel pins 'il are driven through holes lil provided in the side of the barrel l0 and into holes 'i3 provided in the head 69.

A metal reenforcing ring 1t may be placed around opposite ends of the barrel 'l0 to reenforce the edges thereof to prevent damage during handling of the barrel.

This invention thereby provides a process wherein plies of wood can be superimposed upon one another within a suitable form and be expanded outwardly against the Walls of the form to cause the plies to conform to the shape of the form. The plies of wood may shift slightly with respect to one another to arrange themselves in proper order, as determined by the precut arrangement of the plies. If the plies are cut accurately the joint between adjacent staves formed in the plies will be almost imperceptible. However, if the cuts in the ply board forming the .staves should be somewhat inaccurate thc location of the cuts upon an adjacent stave provides a barrel which is leali proof because there is no seam which extends completely through the wall with particular reference to a barrel of convenof the barrel. Even though one of the seams should stand open slightly there can be no leak- It is to be understood that while the process and apparatus herein described has been made tional shape, yet the process and apparatus is applicable to the manufacture of cylindrical j drums or barrels as well as one of conventional shape. If the drum/f or barrel is to be a true cylinder then it would not be necessary to make the V-cuts in the sheets of plywood. The process would therefore be considerably simplified when a cylindrical article was produced. However, the other steps of the process would remain the same.

In Figure 8 there is shown a slightly modified form of apparatus for manufacturing the barrels of this invention. In the apparatus disclosed herein the form 40a is identical with the form 40 disclosed with regard to Figure 5 and the heads 49a. and 50a perform the same function as clisclosed with regard to the apparatus of Figure 5 and are identical inconstruction thereto. Therefore, the elements of Figure 8, which are identical with the elements of Figure 5. bear the same reference numerals but with the suffix a.

Theexpansible'bag disclosed in Figure 8 is modified `from that disclosed in Figure 5 in the manner that a central core 'l5 is provided. The

`expansible bag T6 is disposed around the core l5 somewhat in the manner of an inner tube. The central core l5 lls a portion of the volume of the interior of the barrel form 40a so that it will not beI necessary to introduce as much fluid into the expansible bag It before sufficient pressure is developed therein to expand the ply boards into engagement with the barrel form lila and into engagement with'one another. The apparatus disclosed in Figure 8 therefore shortens the` period required to expand the bag 16 and theref'ore shortens the period of the entire process.

In Figure 9 there is disclosed a modification V wherein a barrel of slightly smaller dimension can be made'. In the apparatus of Figure 9 the barrel form @0b is identical with the construction of the barrel form disclosed in Figure 5. However, in Figure 9 there is shown a series of rings ll which are disposed adjacent the walls Sib and 52h, in the heads 159D and 59h respectively. These rings have the same contour as the walls 5th and 52h but provide a mold wall which is slightly smaller in diameter than the mold wall formed by the walls 5lb and 52D.

The arrangement of Figure 9 thus provides an apparatus whereby a barrel of somewhat smaller dimension can be manufactured than the di..1en sion of the barrel disclosed in Figure 5.

It is to be understood that the apparatus and the method for formim` a barrel as disclosed herein is a preferred method and apparatus. However, there are numerous mechanical modifications which ean be applied to the apparatus, and the steps of the process can be' varied slightly Without departing from the spirit of. the invention, and such modifications are included herein as fall within the scope of the appended claims.

Having thus fully described my invention wha I claim as new and desire to secure hy Letters Patent is:

1. A method of manufacturing a barrel which consists of precutting sheets,y of wood to form a plurality of joined staves, oi disposingv adhesive material between adjacent sheets, of larranging a plurality of sheets within a form having the interior surface in the configuration of a barrel,4

and of expanding the sheets outwardly against the interior surface of the form until the adhesive has set.

2. A method of manufacturing a barrel which consists of precutting sheets of wood to form a plurality of joined staves; of disposing adhesive material between adjacent sheets, of arranging a plurality of sheets within a form having the interior surface in the configuration of a barrel in a manner that the joints between adjacent vtioncd upon the staves of an adjacent sheet. of

disposing adhesive between adjacent sheets, of bending the sheetslongitudinally into the form of a cylinder with the joints of the sheets retained in the prearranged positions, of enclosing the cylinder within a form having the interior surface in the configuration of a barrel. and of expanding the sheets outwardly into engagement with one another and into engagement with the interior surface of the form.

4. A methodv of manufacturing a barrel which consists of precutting sheets of wood to provide a plurality of staves joined substantially at their mid-sections, of positioning a plurality of precut sheets in adjacent relationship with the joints between adjacent staves of one of the sheets positioned upon. the staves of an adjacent sheet, of disposing adhesive' between adjacent sheets, of bending the sheets longitudinally into the form of a cylinder with the joints of the sheets retained in the prearranged positions, of enclosing the cylinder within a form having the interior surface in the configuration of a barrel, of contracting the ends of the cylinder to bring the edges of adjacent staves into abutting relationship, and of expanding the sheets outwardly into engagement with one another and intoengagement with the interior surface of the form.

5. A method of manufacturing a barrel which consists of joining two faces of plywood sheets with the grain thereof running angularly with respect to one another in adjacent sheets, of cutting the plywood sheets in a manner to form a plurality of staves joined together at their mid-sections, of disposing adhesive material adjacent one of the faces of the sheets, of positioning a plurality of precut plywood sheets within a form having the interior surface in the configuration of a barrel and with the join'ts between adjacent staves of one sheet being positioned upon the stave of an adjacent sheet, of

moving the ends of the stavesy with respect to one another toward the axis of the barrel upon axial movement of the form relative to the barrel to be formed thereby until the edges thereof abut one another, and of-'applying pressure to bheinternal surface of the barrel until the adhesive sets.

6. A method of manufacturing a barrel which consists ot joiiing two faces of plywood sheets with the grain thereof running angularly with respect to one another in adjacent sheets. of cutting the plywood sheets in a manner to form a plurality of staves joined together at their midsections. of disposing adhesive material adjacent one of the faces of the sheets, of positioning a plurality of sheets in adjacent relationship with the joints between adjacent staves in one sheet being positioned upon the stavesof an adjacent sheet, of forming the sheets into a cylinder in their prearranged relationship, of contracting the ends of the cylinder until the edges of adjacent staves abut each other, of applying internal pressure to the interior surface of the barrel, and of applying heat to the barrel lto cause the adhesive to set.

7. A method of manufacturinga. barrelcomprising cutting sheets of plywood to'form a plurality of staves arranged in adjacent relationship and joined at their mid sections, of positioning a plurality of sheets in adjacent rela.- tionship so that the joints between adjacent staves of one sheet are disposed upon the staves of an adjacent sheet, of disposing adhesive between adjacent sheets,of transversely bending the sheets to form a cylinder, of slightly con-- tracting the ends of the cylinder, of placing the the internal surface of the barrel to expand the outer surface into engagement with the inner.

surface of the form until the adhesive is set.

8. A method of manufacturing a barrel coml prising cutting sheets of plywood to form a plurality of staves arranged in adjacent relationship and joined at their mid-sections, of positioning a pluralityof sheets in adjacent relationship so thatthe joints between the staves of one sheet are disposed upon the staves of an adjacent sheet, of disposing adhesive between adjacent sheets.. of transversely bending the sheets to form a cylinder, of slightly contracting the ends of the cylinder, of placing the cylinder within a form having the interior surface in the configuration of a barrel, of releasing the ends of the cylinder to permit engagement with the interior surface of the form, of completely contracting the ends of the cylinder until the edges of adjacent staves are in abutting relationship, and of applying pressure uponthe internal surface of the barrel to cause the sheets of plywood to move outwardly toward the inner surface of the form until the outer surface of the outermost sheet in the form engages the inner surface of the form and each subsequent inner sheet engages the outer sheet adjacent thereto, the various sheets shifting with respect to one another until they are in engagement throughout their entire surface until the adhesive is Set.-

9. A method of manufacturing a barrel comprising face joining sheets of wood having the grain thereof disposed angularly in the adjacent sheets, of placing substantially V-shaped cuts in opposite edges of the sheets to form a plurality of joined staves positioned in adjacent relationship, of disposing a plurality of precut sheets in adjacent relationship having the V- tween adiacentsheets. of rolling the sheets into the form i a cylinder while retaining their prearranged reiationshm'of placing retaining rings upon said cylinder, oi.' contracting the ends of said cylinder, of placing said cylinder within a form having movable ends having the interior surface in the connguration of a barrel, of re leasing the ends of the cylinder into engagement with the interior surface of the ends of the form, of contracting the ends of the cylinder by movement .of the ends of thedorm toward oneanother until the edaes of adjacent staves are in abutting relationship, and of applying pressure internally within the barrel to retain adjacent sheets in engagement with one another and in l0. A method ofmanufactm'ing a barrel which consists of precutting sheets ot wood to form a plurality 0f Joined staves, of disposing adhesive material between -fadiacent sheets. of arranging a plurality of sheets within a mold fonn having the interior surface in the conguration of.

a barrel, of disposing an expansible membrane within the barrel shaped form produced by the engagement with theform until the adhesive Sets.

` CLARENCE U. aaamspacna. 

